Flash memory cells are well known in the art. Typically they are arranged in an array comprising a plurality of columns and rows. Examples of a flash memory cell are disclosed in a pending U.S. patent application Ser. No. 09/110,096, filed on Jul. 2, 1998, whose disclosure is incorporated by reference. Memory cells are typically arranged in an array. One example of an array is disclosed in U.S. Pat. No. 5,493,534. Negative charge pumps for use in a non-volatile memory array are also well known in the art. See, for example, U.S. Pat. Nos. 4,673,829; 5,406,517; and 5,282,170.